Packaging structure of electroluminescent element, method for manufacturing the same, display device

ABSTRACT

A flexible display panel with an electroluminescent element, a display device, and a manufacturing method for the packaging structure of an electroluminescent element are provided. The flexible display panel comprises: a first flexible substrate, a first metal mesh on the first flexible substrate, a second flexible substrate on the first metal mesh. The bendability and the flexibility of the proposed flexible display panel are significantly enhanced, which helps to improve the flexibility and the bendability of a display device to which the flexible display panel is applied.

RELATED APPLICATION

The present application claims the benefit of Chinese Patent ApplicationNo. 201810116148.X, filed on Feb. 6, 2018, the entire disclosure ofwhich is incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to the field of display technologies,especially to a packaging structure of an electroluminescent element, amethod for manufacturing the same, and a display device.

BACKGROUND

Electroluminescent elements such as organic light emitting diodes(OLEDs) have been widely used currently. Since such light emittingelements are self-luminous elements, a backlight is not necessary for adisplay device to which an electroluminescence element is applied. Foran organic light emitting diode (OLED), its working principle is thatpositive and negative carriers are injected into the organic lightemitting layer and recombined to generate light. Display devices towhich such light emitting elements are applied have a lot of advantagesin performances and characteristics over liquid crystal displays, suchas excellent shock resistance, high bendability, high brightness, highcontrast, wide viewing angle, ultra-thinness, low cost, low powerconsumption, and the like.

SUMMARY

According to an aspect of the disclosure, there is provided a packagingstructure of an electroluminescent element, comprising: a first flexiblesubstrate, a first metal mesh on the first flexible substrate, and asecond flexible substrate on the first metal mesh. Theelectroluminescent element is located on the second flexible substrate.

In some embodiments, the first metal mesh is enclosed by the firstflexible substrate and the second flexible substrate.

Further, in some embodiments, an orthographic projection of the secondflexible substrate on the first flexible substrate coincides with thefirst flexible substrate and covers an orthographic projection of thefirst metal mesh on the first flexible substrate. A center of theorthographic projection of the first metal mesh on the first flexiblesubstrate coincides with a center of an upper surface of the firstflexible substrate facing the first metal mesh.

In some embodiments, a material of the first metal mesh includesplatinum, platinum-gold alloy or aluminum.

In some embodiments, the packaging structure further comprises a thinfilm packaging layer located on the electroluminescent element.

In some embodiments, the thin film packaging layer includes: a firstpackaging barrier layer located on the electroluminescent element; asecond metal mesh located on the first packaging barrier layer; a secondpackaging barrier layer located on the second metal mesh.

In some embodiments, the second metal mesh is enclosed by the firstpackaging barrier layer and the second packaging barrier layer.

Further, in some embodiments, an orthographic projection of the secondpackaging barrier layer on the first packaging barrier layer coincideswith the first packaging barrier layer and covers an orthographicprojection of the second metal mesh on the first packaging barrierlayer. A center of the orthographic projection of the second metal meshon the first packaging barrier layer coincides with a center of an uppersurface of the first packaging barrier layer facing the second metalmesh.

In some embodiments, the thin film packaging layer further includes abuffer layer located on the second packaging barrier layer.

In some embodiments, the thin film packaging layer further includes athird packaging barrier layer on the buffer layer.

In some embodiments, the packaging structure further comprises: adriving circuit layer between the second flexible substrate and theelectroluminescent element.

In some embodiments, the electroluminescent element comprises an organiclight emitting diode.

Another embodiment of the present disclosure provides a display panelcomprising the packaging structure of an electroluminescent element asdescribed in any of the foregoing embodiments.

Further, a further embodiment of the present disclosure provides adisplay device comprising the display panel described in the foregoingembodiment.

Correspondingly, yet another embodiment of the present disclosureprovides a manufacturing method for a packaging structure of anelectroluminescent element, comprising: forming a first flexiblesubstrate; disposing a first metal mesh on the first flexible substrate;forming a second flexible substrate on the first metal mesh; forming anelectroluminescent element on the second flexible substrate.

Further, in some embodiments, the manufacturing method furthercomprises: forming a first packaging barrier layer on theelectroluminescent element; forming a second metal mesh on the firstpackaging barrier layer; forming a second packaging barrier layer on thesecond metal mesh.

Further, in some embodiments, the manufacturing method furthercomprises: forming a buffer layer on the second packaging barrier layer;forming a third packaging barrier layer on the buffer layer.

It is to be understood that the above general description and thefollowing detailed description are exemplary and illustrative only,which do not limit the scope of the present application.

BRIEF DESCRIPTION OF DRAWINGS

The drawings herein are incorporated into and constitute a part of thespecification, which are used for illustrating the principle of thedisclosure together with embodiments of the specification.

FIG. 1 is a view illustrating a packaging structure of anelectroluminescent element according to an embodiment of the presentdisclosure;

FIG. 2 is a view illustrating the structure of a first metal meshaccording to an embodiment of the present disclosure;

FIG. 3 is a view illustrating a packaging structure of anelectroluminescent element according to another embodiment of thepresent disclosure;

FIG. 4 is a flow chart of a manufacturing method for a packagingstructure of an electroluminescent element according to an embodiment ofthe present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Exemplary embodiments will be described in detail herein, examples ofwhich are illustrated in the accompanying drawings. Where thedescription below refers to the accompanying drawings, the samereference numeral in different drawings denotes the same or similarelements, unless defined otherwise. The exemplary embodiments describedbelow are not intended to represent all possible embodiments that applythe inventive concept revealed by the disclosure, but rather, they areonly some examples of products and methods that are described in detailin the appended claims and embody the inventive concept of thedisclosure.

The inventors of the application have realized that, the substrate, theOLED element, and the packaging layer in a common OLED packagingstructure typically include a polymer material (e.g., plastic) and anorganic/inorganic chemical layer, and the entire packaging structure forthe OLED element has limited bendability, can hardly withstand multiple,wide-angle bends, and has poor restorability after bending.

FIG. 1 shows a packaging structure of an electroluminescent elementaccording to an embodiment of the disclosure. The packaging structurecomprises a first flexible substrate 11, a first metal mesh 12, a secondflexible substrate 13, and an electroluminescent element (e.g., an OLED)14. As shown in FIG. 1, the first metal mesh 12 is located between thefirst flexible substrate 11 and the second flexible substrate 13. Theelectroluminescent element 14 is located on the second flexiblesubstrate 13.

In this embodiment, because the first metal mesh 12 is arranged betweenthe first flexible substrate 11 and the second flexible substrate 13,and the metal material is characterized by its high flexibility, thebendability of the entire packaging structure of the electroluminescentelement can be enhanced, which improves the flexibility of the packagingstructure without badly affecting the adhesiveness between the firstflexible substrate 11 and the second flexible substrate 13.

According to some embodiments of the disclosure, as shown in FIG. 1, thefirst metal mesh 12 is enclosed by the first flexible substrate 11 andthe second flexible substrate 13. In this way, the first metal mesh 12can be brought into close contact with the first flexible substrate 11and the second flexible substrate 13. Further, as shown in FIG. 1, in anembodiment, the area of the first metal mesh 12 is smaller than the areaof the first flexible substrate 11, and the first metal mesh 12 may belocated in the center of the first flexible substrate 11. Specifically,the center point of the first metal mesh 12 may coincide with the centerpoint of the upper surface of the first flexible substrate 11 facing thesecond flexible substrate in the vertical direction. The area of thesecond flexible substrate 13 is the same as that of the first flexiblesubstrate 11, and the second flexible substrate 13 covers the firstmetal mesh 12. In this embodiment, the area of the first flexiblesubstrate 11 refers to the area of the upper surface of the firstflexible substrate 11 facing the first metal mesh 12, and the area ofthe first metal mesh 12 refers to the area of a region on the uppersurface of the first flexible substrate 11 which is occupied by thefirst metal mesh 12. That is, in this embodiment, the orthographicprojection of the second flexible substrate on the first flexiblesubstrate coincides with the first flexible substrate and covers theorthographic projection of the first metal mesh on the first flexiblesubstrate. Further, the center of the orthographic projection of thefirst metal mesh on the first flexible substrate coincides with thecenter of the upper surface of the first flexible substrate facing thefirst metal mesh. In this way, the first metal mesh is confined to acentral position between the first flexible substrate and the secondflexible substrate, which facilitates to achieve uniform improvement ofthe flexibility of the packaging structure and can prevent displacementof the first metal mesh after the packaging structure has been bentmultiple times.

In an embodiment, the material of the first metal mesh 12 may includeplatinum, platinum-gold alloy or aluminum, etc. As a result, an enhancedflexibility of the first metal mesh 12 can be achieved.

An example of the structure of the first metal mesh 12 is shown in FIG.2, but is not limited to the structure shown in FIG. 2. In FIG. 2, metalwires of the first metal mesh 12 are interlaced with each other to forma rectangular hollow structure.

As shown in FIG. 1, in an embodiment, the packaging structure of anelectroluminescent element may further comprise a thin film packaginglayer 15 covering the electroluminescent element 14. In an embodiment,the thin film packaging layer 15 may be a transparent film layer.

As shown in FIG. 1, in an embodiment, the thin film packaging layer 15may include a first packaging barrier layer 151, a second metal mesh152, and a second packaging barrier layer 153. The first packagingbarrier layer 151 is on the electroluminescent element 14, the secondmetal mesh 152 is on the first packaging barrier layer 151, and thesecond packaging barrier layer 153 is on the second metal mesh 152.

Due to the mesh structure of the second metal mesh 152, and because themetal material has high flexibility, by arranging the second metal mesh152 between the first packaging barrier layer 151 and the secondpackaging barrier layer 153, the bendability of the entire packagingstructure of the electroluminescent element can be further enhanced,which further improves the flexibility of the packaging structure.Meanwhile, the arrangement of the second metal mesh will not badlyaffect the adhesiveness between the first packaging barrier layer 151and the second packaging barrier layer 153.

According to some embodiments of the disclosure, the second metal mesh152 is enclosed by the first packaging barrier layer 151 and the secondpackaging barrier layer 153. In an embodiment, the second metal mesh 152may have a structure similar to that is shown in FIG. 2, but is notlimited to the structure shown in FIG. 2.

In an embodiment, the first packaging barrier layer 151 and the secondpackaging barrier layer 153 are both configured to block gas or liquidcomponents such as water and oxygen in an external environment. Thematerials forming the first packaging barrier layer and the secondpackaging barrier layer include, but are not limited to Al₂O₃, TiO₂,ZrO₂, MgO, HFO₂, Ta₂O₅, Si₃N₄, AlN, SiN, SiNO, SiO, SiO₂, SiC, SiCN_(x),ITO, IZO, and the like. The material of the second metal mesh 152 mayinclude platinum, platinum-gold alloy or aluminum, etc.

As shown in FIG. 1, in an embodiment, the area of the second metal mesh152 is smaller than the area of the first packaging barrier layer 151,and the second metal mesh 152 is located on the center of the firstpackaging barrier layer 151. Specifically, the center of the secondmetal mesh 152 may coincide with the center of the upper surface of thefirst packaging barrier layer 151 facing the second packaging barrierlayer in the vertical direction. The area of the second packagingbarrier layer 153 is the same as the area of the first packaging barrierlayer 151. The second packaging barrier layer 153 covers the secondmetal mesh 152. The area of the first packaging barrier layer 151 refersto the area of the upper surface thereof facing the second metal mesh152, and the area of the second packaging barrier layer 153 refers tothe area of the surface thereof away from the second metal mesh 152.Therefore, in some embodiments, the orthographic projection of thesecond packaging barrier layer on the first packaging barrier layercoincides with the first packaging barrier layer and covers theorthographic projection of the second metal mesh on the first packagingbarrier layer. Moreover, the center of the orthographic projection ofthe second metal mesh on the first packaging barrier layer coincideswith the center of the upper surface of the first packaging barrierlayer facing the second metal mesh. In this way, the second metal meshcan be confined to a central position between the second packagingbarrier layer and the first packaging barrier layer, so that the secondmetal mesh contributes to uniform improvement of the flexibility of thepackaging structure, and displacement of the second metal mesh after thepackaging structure has been bent multiple times can be prevented.

As shown in FIG. 1, in an embodiment, the thin film packaging layer 15further includes a buffer layer 154 and a third packaging barrier layer155. The buffer layer 154 is located on the second packaging barrierlayer 153, and the third packaging barrier layer 155 is located on thebuffer layer 154. The third packaging barrier layer 155 is configured toblock water and oxygen, and the material thereof may be the same as thematerial of the first packaging barrier layer 151. The material of thebuffer layer 154 may include a transparent conductive resin, thus thebuffer layer 154 has high elasticity and may facilitate to suppresscracking of the packaging barrier layers (the first packaging barrierlayer 151, the second packaging barrier layer 153, and the thirdpackaging barrier layer 155) and release stresses between inorganiclayers.

As shown in FIG. 3, in an embodiment, the packaging structure of theelectroluminescent element further comprises a driving circuit layer 16.The driving circuit layer 16 is located between the second flexiblesubstrate 13 and the electroluminescent element 14, for driving theelectroluminescent element 14. The driving circuit layer may includecircuit structures such as a thin film transistor (TFT) and itsassociated electrical components. It can be appreciated that theelectroluminescent element referred to in the disclosure may be any typeof electroluminescent element in the art including, but not limited to,an OLED, an LED, and the like.

Another embodiment of the present disclosure provides a display panelcomprising the packaging structure described in any of the foregoingembodiments.

A further embodiment of the disclosure proposes a display devicecomprising the display panel described in the foregoing embodiment. Thedisplay device in this embodiment may be any product or component havinga display function, such as an electronic paper, a mobile phone, atablet computer, a television, a notebook computer, a digital photoframe, a navigator, and the like.

Since the flexibility and the bendability of the packaging structure ofthe electroluminescent element is enhanced, the flexibility of thedisplay panel and the display device to which such a packaging structureis applied can also be improved. Due to the improvement of thebendability of a flexible display device, the lifetime thereof isprolonged.

As shown in FIG. 4, an embodiment of the present disclosure furtherprovides a manufacturing method for a packaging structure of anelectroluminescent element, comprising the following steps 401 to 404:

in step 401, forming a first flexible substrate; in step 402, disposinga first metal mesh on the first flexible substrate; in step 403, forminga second flexible substrate on the first metal mesh; in step 404,forming an electroluminescent element on the second flexible substrate.

The first metal mesh is disposed between the first flexible substrateand the second flexible substrate, and the metal material ischaracterized by high flexibility, so the bendability of the fabricatedpackaging structure of the electroluminescent element can be enhanced,which improves the flexibility of the packaging structure.

In some embodiments, the processes for forming the various layers of thepackaging structure may include a film formation process such asdeposition, sputtering, and the like, and a patterning process such asetching.

In another embodiment, the manufacturing method for a packagingstructure of an electroluminescent element further comprises: forming afirst packaging barrier layer on the electroluminescent element; forminga second metal mesh on the first packaging barrier layer; forming asecond packaging barrier layer on the second metal mesh. Further, inanother embodiment, the manufacturing method further comprises: forminga buffer layer on the second packaging barrier layer; forming a thirdpackaging barrier layer on the buffer layer.

In the drawings, the dimensions of layers and regions may be exaggeratedfor clarity of illustration. Moreover, it should be understood that whenan element or layer is referred to as being “on” or “above” anotherelement or layer, it may be directly on said another element, or anintermediate layer may be present. In addition, it should be understoodthat when an element or layer is referred to as being “under” or “below”another element or layer, it may be directly below said another element,or more than one intermediate layer or element may be present. Inaddition, when a layer or element is referred to as being “between” twolayers or two elements, it may be a single layer between two layers ortwo elements, or more than one intermediate layer or element may befurther present. In the disclosure, the terms “first” and “second” areused for descriptive purposes only and are not to be construed asindicating or implying relative importance. The term “a plurality of”and “multiple” refer to two or more, unless specifically definedotherwise.

The scope of the application is not limited to the embodiments describedherein, but is intended to encompass these embodiments as well as othervariant embodiments, usages or adaptations, etc. that are readilyavailable to those skilled in the art after knowing the contentsdisclosed by the present disclosure and the embodiments. These variantembodiments, usages or adaptations follow the general principles of thepresent disclosure and contain common knowledge or conventionaltechnical measures in this technical field that are not mentionedherein. Accordingly, the specification and embodiments are to beregarded as illustrative only, and the real scope and spirit of thedisclosure are indicated by the appended claims.

To sum up, the present application is not limited to the specificstructures that have been described above and shown in the drawings.Various modifications and variations can be made by those skilled in theart without departing from the essential sprit of the presentdisclosure. The scope of the present application is defined by theappended claims.

1. A flexible display panel comprising an electroluminescent element,the flexible display panel comprising: a first flexible substrate; afirst metal mesh on the first flexible substrate; and a second flexiblesubstrate on the first metal mesh.
 2. The flexible display panelaccording to claim 1, wherein the first metal mesh is between the firstflexible substrate and the second flexible substrate.
 3. The flexibledisplay panel according to claim 2, wherein an orthographic projectionof the second flexible substrate on the first flexible substratecoincides with the first flexible substrate and overlaps an orthographicprojection of the first metal mesh on the first flexible substrate. 4.The flexible display panel according to claim 1, wherein a material ofthe first metal mesh comprises platinum, platinum-gold alloy oraluminum.
 5. The flexible display panel according to claim 1, whereinthe flexible display panel further comprises a thin film packaging layeron the electroluminescent element.
 6. The flexible display panelaccording to claim 5, wherein the thin film packaging layer comprises: afirst packaging barrier layer on the electroluminescent element; asecond metal mesh on the first packaging barrier layer; and a secondpackaging barrier layer on the second metal mesh.
 7. The flexibledisplay panel according to claim 6, wherein the second metal mesh isbetween the first packaging barrier layer and the second packagingbarrier layer.
 8. The flexible display panel according to claim 7,wherein an orthographic projection of the second packaging barrier layeron the first packaging barrier layer coincides with the first packagingbarrier layer and overlaps an orthographic projection of the secondmetal mesh on the first packaging barrier layer.
 9. The flexible displaypanel according to claim 7, wherein the thin film packaging layerfurther comprises a buffer layer on the second packaging barrier layer.10. The flexible display panel according to claim 9, wherein the thinfilm packaging layer further comprises a third packaging barrier layeron the buffer layer.
 11. The flexible display panel according to claim1, wherein the packaging structure further comprises a driving circuitlayer between the second flexible substrate and the electroluminescentelement.
 12. The flexible display panel according to claim 1, whereinthe electroluminescent element comprises an organic light emittingdiode.
 13. (canceled)
 14. A display device comprising the flexibledisplay panel according to claim
 1. 15. A manufacturing method for apackaging structure of an electroluminescent element, comprising:forming a first flexible substrate; forming a first metal mesh on thefirst flexible substrate; forming a second flexible substrate on thefirst metal mesh; and forming the electroluminescent element on thesecond flexible substrate.
 16. The manufacturing method according toclaim 15, further comprising: forming a first packaging barrier layer onthe electroluminescent element; forming a second metal mesh on the firstpackaging barrier layer; and forming a second packaging barrier layer onthe second metal mesh.
 17. The manufacturing method according to claim16, further comprising: forming a buffer layer on the second packagingbarrier layer; and forming a third packaging barrier layer on the bufferlayer.
 18. The flexible display panel according to claim 1, wherein theelectroluminescent element is on the second flexible substrate.
 19. Theflexible display panel according to 10, wherein a material of the firstpackaging barrier layer, the second packaging barrier layer or the thirdpackaging barrier layer comprises as least one selected from a groupcomprising Al₂O₃, TiO₂, ZrO₂, MgO, HFO₂, Ta₂O₅, Si₃N₄, AlN, SiN, SiNO,SiO, SiO₂, SiC, SiCN_(x), ITO and IZO.
 20. The flexible display panelaccording to 9, wherein a material of the buffer layer comprises atransparent conductive resin.